diff --git a/src/class/msc/msc_device.c b/src/class/msc/msc_device.c
index c10fd8a69..ec804dcc8 100644
--- a/src/class/msc/msc_device.c
+++ b/src/class/msc/msc_device.c
@@ -72,8 +72,8 @@ typedef struct {
   uint8_t  ep_out;
 
   uint8_t  stage;
-  uint16_t data_len;
-  uint16_t xferred_len; // numbered of bytes transferred so far in the Data Stage
+  uint32_t data_len;
+  uint32_t xferred_len; // numbered of bytes transferred so far in the Data Stage
 }mscd_interface_t;
 
 CFG_TUSB_ATTR_USBRAM CFG_TUSB_MEM_ALIGN static mscd_interface_t _mscd_itf;
@@ -225,8 +225,10 @@ tusb_error_t mscd_xfer_cb(uint8_t rhport, uint8_t ep_addr, tusb_event_t event, u
         }
         else
         {
-          p_msc->data_len = tud_msc_scsi_cb(rhport, p_cbw->lun, p_cbw->command, _mscd_buf, p_msc->data_len);
-          p_csw->status   = (p_msc->data_len >= 0) ? MSC_CSW_STATUS_PASSED : MSC_CSW_STATUS_FAILED;
+          int32_t const cb_result = tud_msc_scsi_cb(rhport, p_cbw->lun, p_cbw->command, _mscd_buf, p_msc->data_len);
+
+          p_csw->status   = (cb_result >= 0) ? MSC_CSW_STATUS_PASSED : MSC_CSW_STATUS_FAILED;
+          p_msc->data_len = (uint32_t) cb_result;
 
           TU_ASSERT( p_cbw->xfer_bytes >= p_msc->data_len, TUSB_ERROR_INVALID_PARA ); // cannot return more than host expect
 
@@ -329,14 +331,16 @@ tusb_error_t mscd_xfer_cb(uint8_t rhport, uint8_t ep_addr, tusb_event_t event, u
 
   if ( p_msc->stage == MSC_STAGE_STATUS )
   {
-    // Invoke Complete Callback if defined
+    // Invoke complete callback if defined
     if ( SCSI_CMD_READ_10 == p_cbw->command[0])
     {
       if ( tud_msc_read10_complete_cb ) tud_msc_read10_complete_cb(rhport, p_cbw->lun);
-    }else if ( SCSI_CMD_WRITE_10 == p_cbw->command[0] )
+    }
+    else if ( SCSI_CMD_WRITE_10 == p_cbw->command[0] )
     {
       if ( tud_msc_write10_complete_cb ) tud_msc_write10_complete_cb(rhport, p_cbw->lun);
-    }else
+    }
+    else
     {
       if ( tud_msc_scsi_complete_cb ) tud_msc_scsi_complete_cb(rhport, p_cbw->lun, p_cbw->command);
     }
diff --git a/src/portable/nordic/nrf5x/dcd_nrf5x.c b/src/portable/nordic/nrf5x/dcd_nrf5x.c
index 3d3fbdc80..d987cac7b 100644
--- a/src/portable/nordic/nrf5x/dcd_nrf5x.c
+++ b/src/portable/nordic/nrf5x/dcd_nrf5x.c
@@ -263,7 +263,7 @@ static void xact_out_dma(uint8_t epnum)
 /*------------- Bulk/Int IN transfer -------------*/
 
 /**
- * Prepare Bulk/Int in transaction, transfer data from Memory -> Endpoint
+ * Prepare Bulk/Int in transaction, use DMA to transfer data from Memory -> Endpoint
  * @param epnum
  */
 static void xact_in_prepare(uint8_t epnum)
@@ -415,8 +415,8 @@ void USBD_IRQHandler(void)
   if ( int_status & USBD_INTEN_EP0SETUP_Msk )
   {
     uint8_t setup[8] = {
-        NRF_USBD->BMREQUESTTYPE, NRF_USBD->BREQUEST, NRF_USBD->WVALUEL, NRF_USBD->WVALUEH,
-        NRF_USBD->WINDEXL, NRF_USBD->WINDEXH, NRF_USBD->WLENGTHL, NRF_USBD->WLENGTHH
+        NRF_USBD->BMREQUESTTYPE , NRF_USBD->BREQUEST, NRF_USBD->WVALUEL , NRF_USBD->WVALUEH,
+        NRF_USBD->WINDEXL       , NRF_USBD->WINDEXH , NRF_USBD->WLENGTHL, NRF_USBD->WLENGTHH
     };
 
     dcd_setup_received(0, setup);
@@ -486,6 +486,8 @@ void USBD_IRQHandler(void)
         dcd_xfer_complete(0, epnum, xfer->actual_len, true);
       }
     }
+
+    // Ended event for Bulk/Int : nothing to do
   }
 
   if ( int_status & USBD_INTEN_EPDATA_Msk)